Testing of electron beam irradiated sheep wool for adsorption of Cr(III) and Co(II) of higher concentrations

Abstract

Electron beam irradiated sheep wool dosed (0–410) kGy showing good adsorption properties was tested for Cr(III) and Co(II) of higher concentrations. Fitting to ten isotherm models was examined as follows: Langmuir, Freundlich, Dubinin-Radushkevich, Temkin, Flory-Huggins, Halsey, Harkins-Jura, Jovanovic, Elovich and Redlich-Peterson. Both cations being Lewis acids generate complex salts, such as carboxylates or cysteinates, with ligands from keratin. Various composition and architecture of the complexes are responsible for different isotherm model fitting. The chromic cation showed adherence to Freundlich, Temkin, Halsey, Harkins-Jura and Jovanovic models for all or almost all dosed samples unlike cobaltous cation matching Langmuir, Flory-Huggins and Redlich-Peterson isotherm models. No model fitted the both examined cations simultaneously. On the contrary, simultaneously non-fitting to all dosed samples was observed for Elovich and partially Dubinin-Radushkevich models.

Keywords

• Biopolymer
• Electron irradiated sheep wool
• Adsorption
• Cr(III)
• Co(II)
• Isotherm model